Jump to content

Is two pack worth it?


GUMPY

Featured Posts

I will be having my boat painted next year, included in the price is standard blacking, for two pack epoxy its about £1500 extra.

I cant see myself boating much beyond 2025, what attention will two pack need in five years or I will have one blacking to pay for ( £600) if I don't go two pack.

So is two pack worth it? 

Link to comment
Share on other sites

You will get a whole range of opinion on this one, but since it makes sense to have the boat out of the water every 2-3 years to inspect anodes, propeller and everything else sub-aqua, the additional expense of blacking the hull is fairly insignificant.

 

It will come as no surprise that I think 2-pack epoxy is usually a waste of money. As an old bloke in a boatyard once told me "paint scrapes off, blacking smears*. There may be a grain of truth in that.    

 

Since you are anticipating boat ownership for another six years, I think you have just made the economic case for blacking rather than epoxy anyway.

Link to comment
Share on other sites

12 minutes ago, Machpoint005 said:

 

 

As an old bloke in a boatyard once told me "paint scrapes off, blacking smears*. There may be a grain of truth in that.    

 

 

exactly !!   any boat experiencing regular use will be protected better by a self-healing coating.    several decades ago chlorinated rubber paint was the thing to have.  if you gouged it today you would have difficulty finding the mark tomorrow.  that is why proper big ships used it.

Edited by Murflynn
Link to comment
Share on other sites

In terms of simple economics its fairly close but two pack is more expensive. With two pack you need to come out of the water every three or maybe four years against every two years for standard blacking, but a two pack blacking is more expensive, plus the cost of the initial shot blast.

 

In terms of protecting the boat and so extending its life and value then two pack wins hands down. I suspect the only people who say otherwise are those that own a yard or dock that does not offer shotblasting.

 

...............Dave

Link to comment
Share on other sites

2 pack is only worth it if you do little/no actual boating. It chips off, instead of smearing like normal blacking. This means there is in fact no valid extension to maintenance times (out of the water) except for the "no boating" scenario, although of course others will try to persuade you there is.

Link to comment
Share on other sites

14 minutes ago, Machpoint005 said:

 

It will come as no surprise that I think 2-pack epoxy is usually a waste of money. As an old bloke in a boatyard once told me "paint scrapes off, blacking smears*. There may be a grain of truth in that.    

 

 

 

Yes, that is true of paint, but we are talking about two pack epoxy blacking here. :)

 

..............Dave

Link to comment
Share on other sites

Like many things,I expect  it depends on which epoxy. It would certainly be worth a little research to find an epoxy coating that is chip resistant.

 

 My Epidac 2PE seems to be tough stuff so, despite about 5000 hours boating in the last 10  years, including all the BCN, the coating was intact everywhere except the rubbing strakes when surveyed last year.  It has gone rather grey where visible.  Unfortunately it contains coal tar, and is consequently now banned for all practical purposes.

 

A harder grade of "pure" epoxy, as opposed to the epoxy modified pitch of Epidac may well behave differently.  The Camrex we used to trowel onto war canoe flight deckswas certainly prone to chipping if attacked by hard metal objects.

That said I would still go with a tough epoxy, provided I was not intending to sell up in the next 10 years or so.  I would then budget for an underwater exam every 5 years.

 

N

Link to comment
Share on other sites

Having both systems on my two fine craft, I think it depends if you are going to do much more scrapey boating.

Even so I would think it pointless with an older boat that you would have to have shot blasted, unless you are worried about hull side plate thickness.

Barge MA was built with shot blasted epoxy coated steel, so blacking with two pack Hempldur was a no brainer. After a couple of months epoxy goes rock hard so will tend to "ping" off on impact. In 8 years MA has only ever touched bottom once. I am still waiting to get it out of the water for blacking, An "underwater survey" last year on the crystal clear waters of a Shannon tributary showed no flaking or pits in the coating developing (anodes still OK)

Graham at Riversdale never epoxied the hire boats, just out of the water every year to black with Intertuff, to cover up the lack of steering abilities of (most) of his hirers.

NB Earnest has not had an exactly easy 20 year life, but a plating survey last April showed worst side plate thickness 5.6mm. It was never shot blasted and always blacked with Intertuff every 2-3 years. We ended up with two sets of 6 anodes that are replaced in rotation.

 

Having said that our new "retirement" NB Earnest B* will be shot blasted all over and epoxied...it is easy to "down grade" blacking system.

 

NB Earnest B* will have straight hull sides, so 2 pack epoxy black right up to side panels, as well as some extra strategically placed rubbing stakes.

 

 

Link to comment
Share on other sites

44 minutes ago, Murflynn said:

exactly !!   any boat experiencing regular use will be protected better by a self-healing coating.    several decades ago chlorinated rubber paint was the thing to have.  if you gouged it today you would have difficulty finding the mark tomorrow.  that is why proper big ships used it.

 

Except bitumen based blacking doesn't "self-heal", it just gets scraped off too. Any paint system on a heavy steel boat will fail if subjected to impacts against concrete, but bitumen will also fail at the waterline by itself and is badly susceptible to UV cracking too. Big ships may have used chlorinated rubber in the past but what do they use now?

  • Greenie 1
Link to comment
Share on other sites

48 minutes ago, dmr said:

In terms of simple economics its fairly close but two pack is more expensive. With two pack you need to come out of the water every three or maybe four years against every two years for standard blacking, but a two pack blacking is more expensive, plus the cost of the initial shot blast.

 

In terms of protecting the boat and so extending its life and value then two pack wins hands down. I suspect the only people who say otherwise are those that own a yard or dock that does not offer shotblasting.

 

...............Dave

 

It also depends on how the job is done. I put on 4 coats of two pack 4 years ago and I'm not planning to come out until next year just to have a look. I once pressure washed a Thames passenger boat that had been epoxied 10 years earlier and had never been redone and it was almost perfect. They always deployed fenders in locks so never scraped the hull.

Link to comment
Share on other sites

Properly prepared and applied epoxy bitumen does not “chip off” etc. Nor does it abrade easily. We had ours done in 2012 and took it out in 2017 for a look, but unnecessary. Even after many, many locks. Once cleaned up, you couldn’t even see where the waterline was. Also not affected by diesel etc. “Normally” blacked boats seem to spend 1/2 their lives with rusty waterlines. Epoxy blacked ones do not.

 

The blacking pigment can fade though, to a sort of grey or grey brown, although I think this depends on the make.

 

Our hull after 5.5 years, after sanding to put on an extra coat (which wasn’t really necessary).

 

9E526798-A579-4AB7-99BD-1880705B1A5B.png.3642c175e204a1a2043899aa2577af7a.png

Edited by nicknorman
  • Greenie 3
Link to comment
Share on other sites

49 minutes ago, Paul C said:

2 pack is only worth it if you do little/no actual boating. It chips off, instead of smearing like normal blacking. This means there is in fact no valid extension to maintenance times (out of the water) except for the "no boating" scenario, although of course others will try to persuade you there is.

 

Yes I'm one of those others and I disagree with you.. If 2 pack hits concrete it doesn't chip off. That's a myth. It will get scraped and may get damaged but I've worked on boats that moved a lot and it never chipped off. I've hit a few things on my own two packed boat and it's suffered no more than a light scrape but didn't go through to the steel. There certainly is a valid extension to maintenance times if two pack is applied properly, and most of the people who tell you otherwise have no experience of actually using it.

53 minutes ago, Murflynn said:

it's question of hardness - chipping instead of just smearing.  epoxy is very hard, and will chip as a result. 

 

How come my 4 year old two pack has never chipped then? I've moved enough and hit enough things to know.

Link to comment
Share on other sites

36 minutes ago, BEngo said:

Like many things,I expect  it depends on which epoxy. It would certainly be worth a little research to find an epoxy coating that is chip resistant.

 

 

My Jotamastic 87 is hard but not brittle. I think perhaps that's where people are getting confused between two different material properties. Hardness and brittleness are two different things.

Link to comment
Share on other sites

I wouldn't pay the idiotic prices that are asked for 2 pack. There so many other things that can go wrong under the water , especially at the back end, that it's only common sense to take the boat out every couple of years. If it's out of the water then I get my boat blacked.

  • Greenie 1
Link to comment
Share on other sites

57 minutes ago, Murflynn said:

it's question of hardness - chipping instead of just smearing.  epoxy is very hard, and will chip as a result. 

 

The folk who design two pack epoxies for use on boat hulls and other underwater structures do understand stuff like this so formulate their epoxies to be hard but not brittle, and even to have a degree of flexibility to cope with a bit of steel movement. I note that some scrapes even cut a little way into the epoxy but do not go right back to bare steel.

 

We had standard blacking on for about 4 years (which we did ourselves) and now have had epoxy on for 8 years, including two "maintenance dockings" so I am starting to understand how it performs. I am impressed and at the next docking will get the baseplate done too.

 

.............Dave

Link to comment
Share on other sites

26 minutes ago, blackrose said:

 

It also depends on how the job is done. I put on 4 coats of two pack 4 years ago and I'm not planning to come out until next year just to have a look. I once pressure washed a Thames passenger boat that had been epoxied 10 years earlier and had never been redone and it was almost perfect. They always deployed fenders in locks so never scraped the hull.

I suspect that if we did a lot of Thames boating and took a winter mooring then 7 to 10 years would be a reasonable minimum life for epoxy. However we usually do about 1000 miles each year, quite a bit on narrow canals including Brum, and so we get some scrapes. I don't want to be all fussy about boating like some Sea Otter owners :), we use the boat hard, and I quite enjoy the dry-dockings but that's because Stone has some good pubs. Next time need to find a yard that does the baseplate and has good pubs.

 

..............Dave

Link to comment
Share on other sites

To add some detail. Boat is being blasted back to bare steel above the blacking and being given a "dusting" below to remove loose stuff. The £1500 is for full blasting of the underwater area and two pack. 

Apart from the extra cost one thing that puts me off two pack is the damage factor from chains along the Nene locks, I am not boating with fenders down or deploying fenders at every lock ;)

At present boat is done in Keelblack its two years old and holding up well. If I need to take the boat out every 3-4 years with TP then its just not worth doing cost wise as I might as well spend the extra £200 and black it every time rather than £1500 next year.

  • Greenie 1
Link to comment
Share on other sites

1 hour ago, blackrose said:

 

Yes I'm one of those others and I disagree with you.. If 2 pack hits concrete it doesn't chip off. That's a myth. It will get scraped and may get damaged but I've worked on boats that moved a lot and it never chipped off. I've hit a few things on my own two packed boat and it's suffered no more than a light scrape but didn't go through to the steel. There certainly is a valid extension to maintenance times if two pack is applied properly, and most of the people who tell you otherwise have no experience of actually using it.

 

How come my 4 year old two pack has never chipped then? I've moved enough and hit enough things to know.

I do have experience of it though. If you hit something hard enough, the paint will scrape through to the steel, no paint is "magical" enough to avoid this. 2 pack paint lasts better than bitumen-based though. Perhaps "chip" isn't the exactly right term to use but the point being, no paint will withstand the forces of a typical hit (or many), on a narrowboat used on narrow canals. Obviously there's a lot of variables on the use of the boat, for example if its mainly based on a river; or a widebeam but less than the width of the double locks, etc etc so its not easy to compare objectively. Its up to the OP to decide if their boat will be used enough to render 2 pack not worth the extra effort. Also, its worth pointing out (as Nick has done) that a boat prepped and painted in 2 pack from new is at an advantage to a bitumen-painted one. Yes, in theory its possible to sandblast all the bitumen paint off, in practice its a time consuming, expensive job to do it and its quite possible, even with high prices, the job is not done perfectly so the 2-pack will not be as good as if from new.

Link to comment
Share on other sites

I am interested in this topic from a personal point of view, as I only have experience of Hempel.

As mentioned our new NB will be shot blasted / epoxied.

What make of 2 pack epoxy have others been using?

XR&D swear by Sherwin Williams, which they have been using for a while now, anyone any experience of this make?

Link to comment
Share on other sites

14 minutes ago, Neil TNC said:

I am interested in this topic from a personal point of view, as I only have experience of Hempel.

As mentioned our new NB will be shot blasted / epoxied.

What make of 2 pack epoxy have others been using?

XR&D swear by Sherwin Williams, which they have been using for a while now, anyone any experience of this make?

Its not going to be easy to get a good answer to this, most boaters will recommend the one they have used. Unless we know of several boats done in the different brands, with equal quality of prep and then several years of similar useage then its all quesswork.

 

The popular ones look to be International  Intertuf 362, Jotamastic 87 (now replaced with Jotamastic 90) and Hempadur (not sure which one)

 

Hempadur is popular with a few yards but maybe they get a good price if they place regular orders? Intertuf was sold by Midland Chandlers. Jotun have a good reputation and bring out new stuff (like Jotmastic 90) which might imply ongoing R&D effort.

 

We were originally done in Intertuf and it lasted ok but had a lfair few scrapes and came off in a couple of places (which might be underwater abrasion). We have now put Jotamastic over the top on our latest maintenance docking but that was recent so I don't know how it will do. Reason for the change is that Intertuf only comes in 20 litre pots whilst Jotamastic is available in 5 litre pots so smaller repairs are more viable. I have a notion that the Intertuf is thicker and harder but no real evidence to back this up.

 

.............Dave

Link to comment
Share on other sites

My boat was 2 packed from new with International Interzone 954.

 

https://www.boatpaint.co.uk/acatalog/International--Interzone-954.html

 

It has been docked every 4 years on average, and touched up where necessary, usuallly on the rubbing strakes.

 

The boat is now 12 years old and is in dry dock being blacked with the same, so I reckon that it is cost effective. In particular, anodes seem to last longer with two pack, particularly as it is rare for much metal to be exposed (other than the baseplate) between docking. My original anodes lasted 10 years.

Edited by cuthound
Clarification
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.